Left atrial appendage closure device

ABSTRACT

A left atrial appendage closure device may include an expandable framework having a plurality of struts joined at a proximal and distal hub. When the framework is fully constrained in a first position, a first segment of struts extends distally from the distal hub parallel to a central longitudinal axis to a first bend and a second segment of struts extends from the first bend proximally. A first amount of the framework is unconstrained in a second position, where the first segment extends distally from the distal hub parallel to the central longitudinal axis to the first bend, the second segment extends from the first bend proximally and radially outward to a second bend, a third segment of struts extends from the second bend proximally and radially inward to a third bend, and a fourth segment of struts extends from the third bend proximally to within the delivery sheath.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.17/857,513, filed Jul. 5, 2022, which claims the benefit of priority ofU.S. Provisional Application No. 63/219,696 filed Jul. 8, 2021, theentire disclosure of which is hereby incorporated by reference.

TECHNICAL FIELD

The disclosure relates generally to medical devices and moreparticularly to medical devices that are adapted for use in percutaneousmedical procedures including implantation into the left atrial appendage(LAA) of a heart.

BACKGROUND

The left atrial appendage is a small organ attached to the left atriumof the heart. During normal heart function, as the left atriumconstricts and forces blood into the left ventricle, the left atrialappendage constricts and forces blood into the left atrium. The abilityof the left atrial appendage to contract assists with improved fillingof the left ventricle, thereby playing a role in maintaining cardiacoutput. However, in patients suffering from atrial fibrillation, theleft atrial appendage may not properly contract or empty, causingstagnant blood to pool within its interior, which can lead to theundesirable formation of thrombi within the left atrial appendage.

Thrombi forming in the left atrial appendage may break loose from thisarea and enter the blood stream. Thrombi that migrate through the bloodvessels may eventually plug a smaller vessel downstream and therebycontribute to stroke or heart attack. Clinical studies have shown thatthe majority of blood clots in patients with atrial fibrillationoriginate in the left atrial appendage. As a treatment, medical deviceshave been developed which are deployed to close off the left atrialappendage. Of the known medical devices and methods, each has certainadvantages and disadvantages. There is an ongoing need to providealternative medical devices and introducers as well as alternativemethods for manufacturing and using medical devices and introducers.

SUMMARY

In one example, a left atrial appendage closure device may comprise anexpandable framework having a plurality of struts disposed about acentral longitudinal axis, the plurality of struts being joined togetherat a proximal hub and a distal hub. When the expandable framework isfully constrained in a first position by a delivery sheath, a firstsegment of the plurality of struts extends distally from the distal hubparallel to the central longitudinal axis to a first bend and a secondsegment of the plurality of struts extends from the first bendproximally. A first amount of the expandable framework is unconstrainedby the delivery sheath in a second position. In the second position thefirst segment of the plurality of struts extends distally from thedistal hub parallel to the central longitudinal axis to the first bend,the second segment of the plurality of struts extends from the firstbend proximally and radially outward to a second bend, a third segmentof the plurality of struts extends from the second bend proximally andradially inward to a third bend, and a fourth segment of the pluralityof struts extends from the third bend proximally to within the deliverysheath.

In addition or alternatively to any example disclosed herein, in thesecond position the first segment and the second segment form an acuteangle opening inwardly toward an interior of the expandable framework.

In addition or alternatively to any example disclosed herein, a secondamount of the expandable framework greater than the first amount isunconstrained by the delivery sheath in a third position. In the thirdposition the first segment of the plurality of struts extends distallyfrom the distal hub parallel to the central longitudinal axis to thefirst bend, the second segment of the plurality of struts extends fromthe first bend radially outward generally perpendicular to the centrallongitudinal axis to the second bend, the third segment of the pluralityof struts extends from the second bend proximally and radially inward tothe third bend, and the fourth segment of the plurality of strutsextends from the third bend proximally toward the proximal hub disposedwithin the delivery sheath.

In addition or alternatively to any example disclosed herein, in thethird position the second segment and the third segment form an acuteangle opening inwardly toward the central longitudinal axis.

In addition or alternatively to any example disclosed herein, in thethird position the third segment and the fourth segment form an obtuseangle opening outwardly away from the central longitudinal axis.

In addition or alternatively to any example disclosed herein, a thirdamount of the expandable framework greater than the second amount isunconstrained by the delivery sheath in a fourth position. In the fourthposition the first segment of the plurality of struts extends distallyfrom the distal hub parallel to the central longitudinal axis to thefirst bend, the second segment of the plurality of struts extends fromthe first bend distally and radially outward to the second bend, thethird segment of the plurality of struts extends from the second bendproximally and radially inward toward the third bend, and the fourthsegment of the plurality of struts extends from the third bendproximally toward the proximal hub disposed within the delivery sheath.

In addition or alternatively to any example disclosed herein, in thefourth position the first segment and the second segment form an obtuseangle opening inwardly toward an interior of the expandable framework.

In addition or alternatively to any example disclosed herein, in thefourth position the second segment and the third segment form an acuteangle opening inwardly toward the central longitudinal axis.

In addition or alternatively to any example disclosed herein, in thefourth position the third segment and the fourth segment form an obtuseangle opening outwardly away from the central longitudinal axis.

In addition or alternatively to any example disclosed herein, a fourthamount of the expandable framework greater than the third amount isunconstrained by the delivery sheath in a fifth position. In the fifthposition the first segment of the plurality of struts extends distallyfrom the distal hub parallel to the central longitudinal axis to thefirst bend, the second segment of the plurality of struts extends fromthe first bend distally and radially outward to the second bend, thethird segment of the plurality of struts extends from the second bendproximally to the third bend, and the fourth segment of the plurality ofstruts extends from the third bend radially inward toward the proximalhub.

In addition or alternatively to any example disclosed herein, in thefifth position the first segment and the second segment form an obtuseangle opening inwardly.

In addition or alternatively to any example disclosed herein, in thefifth position the second segment and the third segment form an acuteangle opening inwardly.

In addition or alternatively to any example disclosed herein, in thefifth position the third segment and the fourth segment form an angle ofabout 90 degrees or less opening inwardly.

In addition or alternatively to any example disclosed herein, the distalhub is disposed proximal of the first bend.

In addition or alternatively to any example disclosed herein, in thesecond position the distal hub is disposed distal of the second bend.

In addition or alternatively to any example disclosed herein, a leftatrial appendage closure device may comprise an expandable frameworkhaving a plurality of struts disposed about a central longitudinal axis,the plurality of struts being joined together at a proximal hub and adistal hub. As the expandable framework shifts from fully constrained tofully unconstrained, the expandable framework transitions sequentiallythrough a plurality of positions. In a first position, a first segmentof the plurality of struts extends distally from the distal hub parallelto the central longitudinal axis to a first bend and a second segment ofthe plurality of struts extends from the first bend proximally andgenerally parallel to the central longitudinal axis. In a secondposition, the second segment of the plurality of struts, if sweptcircumferentially around the central longitudinal axis, defines agenerally conical shape tapering radially outward in a proximaldirection from the first bend toward a second bend.

In addition or alternatively to any example disclosed herein, in thesecond position, the distal hub is disposed proximal of the first bendand the distal hub is disposed distal of the second bend.

In addition or alternatively to any example disclosed herein, in a thirdposition, the second segment of the plurality of struts, if sweptcircumferentially around the central longitudinal axis, defines agenerally planar shape oriented generally perpendicular to the centrallongitudinal axis.

In addition or alternatively to any example disclosed herein, in afourth position, the second segment of the plurality of struts, if sweptcircumferentially around the central longitudinal axis, defines agenerally conical shape tapering radially outward in a distal directionfrom the first bend toward the second bend.

In addition or alternatively to any example disclosed herein, a leftatrial appendage closure device system may comprise a delivery sheathhaving a lumen extending therein, and a left atrial appendage closuredevice comprising an expandable framework having a plurality of strutsdisposed about a central longitudinal axis, the plurality of strutsbeing joined together at a proximal hub and a distal hub. When theexpandable framework is disposed within the lumen of the delivery sheathin a first position, a first segment of the plurality of struts extendsdistally from the distal hub parallel to the central longitudinal axisto a first bend and a second segment of the plurality of struts extendsfrom the first bend proximally. Relative axial translation between thedelivery sheath and the expandable framework exposes some of theexpandable framework in a second position. In the second position thefirst segment of the plurality of struts extends distally from thedistal hub parallel to the central longitudinal axis to the first bend,the second segment of the plurality of struts extends from the firstbend proximally and radially outward to a second bend, a third segmentof the plurality of struts extends from the second bend proximally andradially inward to a third bend, and a fourth segment of the pluralityof struts extends from the third bend proximally to within the deliverysheath. Relative axial translation between the delivery sheath and theexpandable framework exposes more of the expandable framework in a thirdposition than in the second position. In the third position the firstsegment of the plurality of struts extends distally from the distal hubparallel to the central longitudinal axis to the first bend, the secondsegment of the plurality of struts extends from the first bend radiallyoutward generally perpendicular to the central longitudinal axis to thesecond bend, the third segment of the plurality of struts extends fromthe second bend proximally and radially inward to the third bend, andthe fourth segment of the plurality of struts extends from the thirdbend proximally toward the proximal hub disposed within the deliverysheath. Relative axial translation between the delivery sheath and theexpandable framework exposes more of the expandable framework in afourth position than in the third position. In the fourth position thefirst segment of the plurality of struts extends distally from thedistal hub parallel to the central longitudinal axis to the first bend,the second segment of the plurality of struts extends from the firstbend distally and radially outward to the second bend, the third segmentof the plurality of struts extends from the second bend proximally andradially inward toward the third bend, and the fourth segment of theplurality of struts extends from the third bend proximally toward theproximal hub disposed within the delivery sheath. Relative axialtranslation between the delivery sheath and the expandable frameworkexposes all of the expandable framework in a fifth position. In thefifth position the first segment of the plurality of struts extendsdistally from the distal hub parallel to the central longitudinal axisto the first bend, the second segment of the plurality of struts extendsfrom the first bend distally and radially outward to the second bend,the third segment of the plurality of struts extends from the secondbend proximally to the third bend, and the fourth segment of theplurality of struts extends from the third bend radially inward towardthe proximal hub.

The above summary of some embodiments, aspects, and/or examples is notintended to describe each embodiment or every implementation of thepresent disclosure. The figures and the detailed description moreparticularly exemplify aspects of these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure may be more completely understood in consideration of thefollowing detailed description in connection with the accompanyingdrawings, in which:

FIGS. 1-2 are side views of a left atrial appendage closure devicesystem;

FIG. 3 illustrates selected aspects of a left atrial appendage closuredevice;

FIG. 4 illustrates selected aspects of the left atrial appendage closuredevice of FIG. 3 ; and

FIGS. 5-9 are schematic partial cross-sectional views illustratingselected aspects related to deploying the left atrial appendage closuredevice of FIGS. 3-4 .

While aspects of the disclosure are amenable to various modificationsand alternative forms, examples are shown in the drawings and describedherein. It should be understood, however, that the intention is not tolimit aspects of the disclosure to the particular embodiments described.On the contrary, the disclosure shall cover all modifications,equivalents, and alternatives falling within the spirit and scopethereof.

DETAILED DESCRIPTION

The following description should be read with reference to the drawings,which are not necessarily to scale, wherein like reference numeralsindicate like elements throughout the several views. The detaileddescription and drawings are intended to illustrate but not limit thepresent disclosure. Those skilled in the art will recognize that thevarious elements described and/or shown may be arranged in variouscombinations and configurations without departing from the scope of thedisclosure. The detailed description and drawings illustrate exemplaryaspects of the disclosure. However, in the interest of clarity and easeof understanding, while every feature and/or element may not be shown ineach drawing, the feature(s) and/or element(s) may be understood to bepresent regardless, unless otherwise specified.

For the following defined terms, these definitions shall be applied,unless a different definition is given in the claims or elsewhere inthis specification.

All numeric values are herein assumed to be modified by the term“about,” whether or not explicitly indicated. The term “about”, in thecontext of numeric values, generally refers to a range of numbers thatone of skill in the art would consider equivalent to the recited value(e.g., having the same function or result). In many instances, the term“about” may include numbers that are rounded to the nearest significantfigure. Other uses of the term “about” (e.g., in a context other thannumeric values) may be assumed to have their ordinary and customarydefinition(s), as understood from and consistent with the context of thespecification, unless otherwise specified.

The recitation of numerical ranges by endpoints includes all numberswithin that range, including the endpoints (e.g., 1 to 5 includes 1,1.5, 2, 2.75, 3, 3.80, 4, and 5).

Although some suitable dimensions, ranges, and/or values pertaining tovarious components, features and/or specifications are disclosed, one ofskill in the art, incited by the present disclosure, would understanddesired dimensions, ranges, and/or values may deviate from thoseexpressly disclosed.

As used in this specification and the appended claims, the singularforms “a”, “an”, and “the” include plural referents unless the contentclearly dictates otherwise. As used in this specification and theappended claims, the term “or” is generally employed in its senseincluding “and/or” unless the content clearly dictates otherwise. It isto be noted that in order to facilitate understanding, certain featuresof the disclosure may be described in the singular, even though thosefeatures may be plural or recurring within the disclosed embodiment(s).Each instance of the features may include and/or be encompassed by thesingular disclosure(s), unless expressly stated to the contrary. Forsimplicity and clarity purposes, all elements of the present disclosureare not necessarily shown in each figure or discussed in detail below.However, it will be understood that the following discussion may applyequally to any and/or all of the components for which there are morethan one, unless explicitly stated to the contrary. Additionally, notall instances of some elements or features may be shown in each figurefor clarity.

Relative terms such as “proximal”, “distal”, “advance”, “retract”,variants thereof, and the like, may be generally considered with respectto the positioning, direction, and/or operation of various elementsrelative to a user/operator/manipulator of the device, wherein“proximal” and “retract” indicate or refer to closer to or toward theuser and “distal” and “advance” indicate or refer to farther from oraway from the user. In some instances, the terms “proximal” and “distal”may be arbitrarily assigned in an effort to facilitate understanding ofthe disclosure, and such instances will be readily apparent to theskilled artisan. Other relative terms, such as “upstream”, “downstream”,“inflow”, and “outflow” refer to a direction of fluid flow within alumen, such as a body lumen, a blood vessel, or within a device. Stillother relative terms, such as “axial”, “circumferential”,“longitudinal”, “lateral”, “radial”, etc. and/or variants thereofgenerally refer to direction and/or orientation relative to a centrallongitudinal axis of the disclosed structure or device.

The term “extent” may be understood to mean the greatest measurement ofa stated or identified dimension, unless the extent or dimension inquestion is preceded by or identified as a “minimum”, which may beunderstood to mean the smallest measurement of the stated or identifieddimension. For example, “outer extent” may be understood to mean anouter dimension, “radial extent” may be understood to mean a radialdimension, “longitudinal extent” may be understood to mean alongitudinal dimension, etc. Each instance of an “extent” may bedifferent (e.g., axial, longitudinal, lateral, radial, circumferential,etc.) and will be apparent to the skilled person from the context of theindividual usage. Generally, an “extent” may be considered the greatestpossible dimension measured according to the intended usage, while a“minimum extent” may be considered the smallest possible dimensionmeasured according to the intended usage. In some instances, an “extent”may generally be measured orthogonally within a plane and/orcross-section, but may be, as will be apparent from the particularcontext, measured differently—such as, but not limited to, angularly,radially, circumferentially (e.g., along an arc), etc.

The terms “monolithic” and “unitary” shall generally refer to an elementor elements made from or consisting of a single structure or baseunit/element. A monolithic and/or unitary element shall excludestructure and/or features made by assembling or otherwise joiningmultiple discrete structures or elements together.

It is noted that references in the specification to “an embodiment”,“some embodiments”, “other embodiments”, etc., indicate that theembodiment(s) described may include a particular feature, structure, orcharacteristic, but every embodiment may not necessarily include theparticular feature, structure, or characteristic. Moreover, such phrasesare not necessarily referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with an embodiment, it would be within the knowledge of oneskilled in the art to effect the particular feature, structure, orcharacteristic in connection with other embodiments, whether or notexplicitly described, unless clearly stated to the contrary. That is,the various individual elements described below, even if not explicitlyshown in a particular combination, are nevertheless contemplated asbeing combinable or arrangeable with each other to form other additionalembodiments or to complement and/or enrich the described embodiment(s),as would be understood by one of ordinary skill in the art.

For the purpose of clarity, certain identifying numerical nomenclature(e.g., first, second, third, fourth, etc.) may be used throughout thedescription and/or claims to name and/or differentiate between variousdescribed and/or claimed features. It is to be understood that thenumerical nomenclature is not intended to be limiting and is exemplaryonly. In some embodiments, alterations of and deviations from previouslyused numerical nomenclature may be made in the interest of brevity andclarity. That is, a feature identified as a “first” element may later bereferred to as a “second” element, a “third” element, etc. or may beomitted entirely, and/or a different feature may be referred to as the“first” element. The meaning and/or designation in each instance will beapparent to the skilled practitioner.

The left atrial appendage may be attached to and in fluid communicationwith a left atrium of a patient's heart. In some patients, the leftatrial appendage may have a complex geometry and/or irregular surfacearea. Those of skill in the art will also recognize that the medicaldevices and methods disclosed herein may be adapted for various sizesand shapes of the left atrial appendage, as necessary. The left atrialappendage may include a generally longitudinal axis arranged along adepth of a main body of the left atrial appendage. The main body mayinclude a wall and an ostium forming a proximal mouth. In someembodiments, a lateral extent of the ostium and/or the wall may besmaller or less than a depth of the main body along the longitudinalaxis, or a depth of the main body may be greater than a lateral extentof the ostium and/or the wall. In some embodiments, the left atrialappendage may include a tail-like element associated with a distalportion of the main body, which element may protrude radially orlaterally away from the main body.

The following figures illustrate selected components and/or arrangementsof a left atrial appendage closure device, a left atrial appendageclosure device system, and/or methods of using the left atrial appendageclosure device and/or the left atrial appendage closure device system.It should be noted that in any given figure, some features may not beshown, or may be shown schematically, for simplicity. Additional detailsregarding some of the components of the implant and/or the system may beillustrated in other figures in greater detail. While discussed in thecontext of occluding the left atrial appendage, the left atrialappendage closure device and/or the left atrial appendage closure devicesystem may also be used for other interventions and/or percutaneousmedical procedures within a patient. Similarly, the devices and methodsdescribed herein with respect to percutaneous deployment may be used inother types of surgical procedures, as appropriate. For example, in someexamples, the devices may be used in a non-percutaneous procedure.Devices and methods in accordance with the disclosure may also beadapted and configured for other uses within the anatomy.

FIGS. 1-2 illustrate selected components and/or arrangements of a leftatrial appendage closure device system 10 which may be used foroccluding a left atrial appendage. It should be noted that in any givenfigure, some features of the left atrial appendage closure device system10 may not be shown, or may be shown schematically, for simplicity.Additional details regarding some of the components of the left atrialappendage closure device system 10 may be illustrated in other figuresin greater detail.

The left atrial appendage closure device system 10 may include adelivery sheath 40 having a lumen 42 extending from a proximal openingto a distal opening, a core wire 30 slidably disposed within the lumen42, and a left atrial appendage closure device 100 for occluding theleft atrial appendage. The left atrial appendage closure device 100 mayinclude an expandable framework 110 (e.g., FIG. 3 ) configured to shiftbetween a fully constrained configuration (e.g., FIG. 1 ), wherein theleft atrial appendage closure device 100 is disposed within the lumen 42proximate the distal opening in the delivery configuration, and a fullyunconstrained configuration (e.g., FIG. 2 ), wherein the left atrialappendage closure device 100 and/or the expandable framework 110 isconfigured to shift between the fully constrained configuration and thefully unconstrained configuration as the left atrial appendage closuredevice 100 is translated relative to the delivery sheath 40. In at leastsome embodiments, the expandable framework 110 may be self-biased towardthe fully unconstrained configuration.

The left atrial appendage closure device 100 may be disposed at and/orreleasably securable to a distal portion of the core wire 30. The corewire 30 may be slidably and/or rotatably disposed within the lumen 42 ofthe delivery sheath 40. In some embodiments, a proximal end of the corewire 30 may extend proximally of a proximal end of the delivery sheath40 and/or the proximal opening of the lumen 42 for manual manipulationby a clinician or practitioner. In some embodiments, the left atrialappendage closure device 100 may be removably attached, joined, secured,or otherwise connected to a distal end of the core wire 30. The corewire 30 may be configured to and/or may be capable of axiallytranslating the left atrial appendage closure device 100 relative to thedelivery sheath 40. In one example, the core wire 30 may be advanceddistally while the delivery sheath 40 is held in a constant position. Inanother example, the core wire 30 may be advanced distally while thedelivery sheath 40 is retracted proximally. In yet another example, thecore wire 30 may be held in a constant position while the deliverysheath 40 is retracted proximally relative to the core wire 30 and/orthe left atrial appendage closure device 100. Other configurations arealso contemplated. The delivery sheath 40 and/or the core wire 30 mayhave a selected level of axial stiffness and/or pushabilitycharacteristics while also having a selected level of flexibility topermit navigation through the patient's vasculature.

Some suitable, but non-limiting, examples of materials for the leftatrial appendage closure device system 10, the core wire 30, thedelivery sheath 40, and/or the left atrial appendage closure device 100,etc. are discussed below. It is contemplated that any exemplary leftatrial appendage closure device disclosed herein may be used inaccordance with and/or be associated with the example left atrialappendage closure device system 10 described above.

The left atrial appendage closure device 100 may comprise an expandableframework 110 configured to shift axially and/or radially along acentral longitudinal axis between the fully constrained configurationand the fully unconstrained configuration. In the fully constrainedconfiguration, the expandable framework 110 may be axially elongatedand/or radially compressed. In the fully unconstrained configuration,the expandable framework 110 may be axially shortened and/or radiallyexpanded.

As seen in FIG. 3 , which illustrates selected aspects of the leftatrial appendage closure device 100 in the fully unconstrainedconfiguration, the expandable framework 110 may have a plurality ofstruts disposed about the central longitudinal axis. In someembodiments, the plurality of struts may define a plurality of cells. Insome embodiments, the plurality of cells may be a plurality of closedcells. In some embodiments, the plurality of cells may be a plurality ofopen cells. In some embodiments, the plurality of cells may include aplurality of open cells and a plurality of closed cells in variouscombinations and/or arrangements.

The expandable framework 110 may include a proximal hub 112 and a distalhub 114. In some embodiments, the proximal hub 112 and/or the distal hub114 may be centered on and/or coaxial with the longitudinal axis. Theplurality of struts may be joined together at and/or fixedly attached tothe proximal hub 112 and/or the distal hub 114. The proximal hub 112 maybe configured to releasably connect, secure, and/or attach the leftatrial appendage closure device 100 and/or the expandable framework 110to the core wire 30. In some embodiments, the proximal hub 112 mayinclude internal threads configured to rotatably and/or threadablyengage an externally threaded distal end of the core wire 30. Otherconfigurations for releasably securing the left atrial appendage closuredevice 100 to the core wire 30 are also contemplated. As noted herein,some features are not shown in every figure to improve clarity.

The expandable framework 110 and/or the plurality of struts may beformed and/or cut from a tubular member. In some embodiments, theexpandable framework 110 and/or the plurality of struts may beintegrally formed and/or cut from a unitary member. In some embodiments,the expandable framework 110 and/or the plurality of struts may beintegrally formed and/or cut from a unitary tubular member andsubsequently formed and/or heat set to a desired shape in the fullyunconstrained configuration. In some embodiments, the expandableframework 110 and/or the plurality of struts may be integrally formedand/or cut from a unitary flat member or sheet, and then rolled orformed into a tubular structure and subsequently formed and/or heat setto the desired shape in the fully unconstrained configuration. Someexemplary means and/or methods of making and/or forming the expandableframework 110 and/or the plurality of struts include laser cutting,machining, punching, stamping, electro discharge machining (EDM),chemical dissolution, etc. Other means and/or methods are alsocontemplated.

As would be understood by the skilled person, anatomical features mayvary in size and/or shape. In some embodiments, the left atrialappendage may have an irregular (e.g., elongated and/or oblong)cross-sectional shape. In some embodiments, the expandable framework 110may be compliant and substantially conform to and/or be in sealingengagement with the shape and/or geometry of a lateral wall of a leftatrial appendage when deployed and/or expanded therein. In someembodiments, the left atrial appendage closure device 100 may expand toa size, extent, or shape less than or different from the fullyunconstrained configuration, as determined by the surrounding tissueand/or lateral wall of the left atrial appendage. In some embodiments,the expandable framework 110 may be configured to shape and/or stretchthe tissue of the left atrial appendage such that the lateral wall ofthe left atrial appendage substantially conforms to an outer shape ofthe expandable framework 110. Other configurations are alsocontemplated.

In some embodiments, the expandable framework 110 may include at leastone anchoring member 116 extending radially outward therefrom in thefully unconstrained configuration. In some embodiments, the expandableframework 110 may include at least one anchoring member 116 extendingradially outward from the expandable framework 110. In some embodiments,the expandable framework 110 may include at least one anchoring member116 extending radially outward from the expandable framework 110proximate a proximal shoulder of the expandable framework 110. In someembodiments, the expandable framework 110 may include at least oneanchoring member 116 extending radially outward from the expandableframework 110 proximate a midsection of the expandable framework 110. Insome embodiments, the at least one anchoring member 116 may beconfigured to engage with the lateral wall of the main body of the leftatrial appendage. In some embodiments, the at least one anchoring member116 may be formed as J-shaped hooks having a free end extending inand/or directed toward a proximal direction with respect to the centrallongitudinal axis of the left atrial appendage closure device 100 and/orthe expandable framework 110. Other configurations are alsocontemplated.

In some embodiments, the left atrial appendage closure device 100 mayoptionally include the occlusive element 120 connected to, disposed on,disposed over, disposed about, and/or disposed radially outward of atleast a portion of the expandable framework 110 and/or the plurality ofstruts, as seen in FIG. 4 . In some embodiments, the occlusive element120 may be attached to the proximal hub 112 and/or may be attached tothe expandable framework at the proximal hub 112. In some embodiments,the occlusive element 120 may extend radially outward from and/or mayextend distally from the proximal hub 112. In some embodiments, theocclusive element 120 may be attached and/or secured to the expandableframework 110 at a plurality of discrete locations. In some embodiments,one of, some of, and/or all of the at least one anchoring member 116 mayextend through an occlusive element 120, where present.

In some embodiments, the occlusive element 120 may include a membrane, afabric, a mesh, a tissue element, or another suitable construction. Insome embodiments, the occlusive element 120 may be porous. In someembodiments, the occlusive element 120 may be non-porous. In someembodiments, the occlusive element 120 may be permeable to selectedgases and/or fluids. In some embodiments, the occlusive element 120 maybe substantially impermeable to selected gases and/or fluids, such asblood, water, etc. In some embodiments, the occlusive element 120 may bedesigned, sized, and/or configured to prevent thrombus and/or embolicmaterial from passing out of the left atrial appendage into the leftatrium and/or the patient's bloodstream. In some embodiments, theocclusive element 120 may be configured to promote endothelization afterimplantation, thereby effectively removing the target site (e.g., theleft atrial appendage, etc.) from the patient's circulatory system. Somesuitable, but non-limiting, examples of materials for the occlusiveelement 120 are discussed below.

FIGS. 5-9 schematically illustrate selected aspects of the left atrialappendage closure device 100 and/or the left atrial appendage closuredevice system 10 during deployment of the left atrial appendage closuredevice 100. For clarity and ease of understanding, some elements of theleft atrial appendage closure device 100 are not shown but shall beunderstood to be present in accordance and/or consistent with otherfigures and/or description of the disclosure. FIGS. 5-8 illustrate theleft atrial appendage closure device 100 in partial cross-section. FIG.9 illustrates the left atrial appendage closure device 100 using brokenlines to show hidden features as may be understood from other figures.The occlusive element 120 is not shown in FIG. 9 . It may be seen inFIGS. 5-9 that as the expandable framework 110 of the left atrialappendage closure device 100 shifts from fully constrained to fullyunconstrained, the expandable framework 110 may transition sequentiallythrough a plurality of positions. In some embodiments, the plurality ofpositions may include a first position, a second position, a thirdposition, a fourth position, and/or a fifth position as describedherein. In some embodiments, the plurality of positions may includeadditional and/or other positions.

Returning now to FIG. 5 , in some embodiments, the expandable framework110 may be fully constrained in a first position by the delivery sheath40. In some embodiments, the expandable framework 110 may be disposedwithin the lumen 42 of the delivery sheath 40 in the first position. Insome embodiments, in the first position a first segment 130 of theplurality of struts of the expandable framework 110 may extend distallyfrom the distal hub 114 substantially parallel to the centrallongitudinal axis to a first bend 132 and a second segment 140 of theplurality of struts of the expandable framework 110 may extend from thefirst bend 132 proximally. In some embodiments, in the first positionthe second segment 140 may extend from the first bend 132 proximally andgenerally parallel to the central longitudinal axis. In the firstposition, the distal hub 114 may be disposed proximal of the first bend132. In some embodiments, the first segment 130 may be secured to thedistal hub 114. In some embodiments, the first segment 130 may befixedly attached to the distal hub 114. For example, the first segment130 may be welded, adhesively bonded, etc. to the distal hub 114. Otherconfigurations are also contemplated.

In some embodiments, relative axial translation between the deliverysheath 40 and the expandable framework 110 may expose some of theexpandable framework 110 and/or the plurality of struts in a secondposition, as seen in FIG. 6 . In some embodiments, a first amount of theexpandable framework 110 and/or the plurality of struts may be exposedfrom and/or unconstrained by the delivery sheath 40 in the secondposition. In some embodiments, the first amount may be less than about55% of an axial length, a volume, a weight, and/or a surface area of theexpandable framework 110 and/or the plurality of struts. In someembodiments, the first amount may be about 15% to about 55% of the axiallength, the volume, the weight, and/or the surface area of theexpandable framework 110 and/or the plurality of struts. Otherconfigurations and/or ranges are also contemplated. In some embodiments,in the second position, the expandable framework 110 may have a maximumradial extent of about 6 millimeters (mm) to about 10 mm. In someembodiments, in the second position, the expandable framework 110 mayhave a maximum radial extent of about 8 mm. In some embodiments, in thesecond position, the maximum radial extent of the expandable framework110 may be about twice or about 200% of a maximum outer extent of adistal end of the delivery sheath 40. Other configurations and/or sizesare also contemplated.

In some embodiments, in the second position the first segment 130 of theplurality of struts of the expandable framework 110 may extend distallyfrom the distal hub 114 substantially parallel to the centrallongitudinal axis to the first bend 132. In the second position, thesecond segment 140 of the plurality of struts of the expandableframework 110 may extend from the first bend 132 proximally and radiallyoutward toward and/or to a second bend 142. In the second position, athird segment 150 of the plurality of struts of the expandable framework110 may extend from the second bend 142 proximally and radially inwardtoward and/or to a third bend 152. In some embodiments, in the secondposition, a fourth segment 160 of the plurality of struts of theexpandable framework 110 may extend from the third bend 152 proximallyto within the lumen 42 of the delivery sheath 40. In some embodiments,in the second position, the fourth segment 160 of the plurality ofstruts of the expandable framework 110 may extend from the third bend152 proximally toward the proximal hub 112 disposed within the lumen 42of the delivery sheath 40.

In some embodiments, in the second position, the distal hub 114 isdisposed proximal of the first bend 132. In some embodiments, in thesecond position, the distal hub 114 may be disposed distal of the secondbend 142. For example, in the second position, the distal hub 114 may bepositioned distal of a plane extending through, including at least aportion of, and/or tangent to the second bend 142 and orientedperpendicular to the central longitudinal axis. In some embodiments, inthe second position, the first segment 130 of the plurality of strutsand the second segment 140 of the plurality of struts may form and/orintersect to form an acute angle opening inwardly toward an interior ofthe expandable framework 110. In some embodiments, in the secondposition, the first segment 130 of the plurality of struts and thesecond segment 140 of the plurality of struts may form and/or intersectto form an acute angle opening radially outwardly from the centrallongitudinal axis. In some embodiments, in the second position, thesecond segment 140 of the plurality of struts of the expandableframework 110, if swept circumferentially around the centrallongitudinal axis, may define a generally conical shape taperingradially outward in a proximal direction from the first bend 132 towardthe second bend 142.

In some embodiments, relative axial translation between the deliverysheath 40 and the expandable framework 110 may expose more of theexpandable framework 110 and/or the plurality of struts in a thirdposition than in the second position, as seen in FIG. 7 . In someembodiments, a second amount of the expandable framework 110 and/or theplurality of struts greater than the first amount may be exposed fromand/or unconstrained by the delivery sheath 40 in the third position. Insome embodiments, the second amount may be less than about 75% of theaxial length, the volume, the weight, and/or the surface area of theexpandable framework 110 and/or the plurality of struts. In someembodiments, the second amount may be about 40% to about 75% of theaxial length, the volume, the weight, and/or the surface area of theexpandable framework 110 and/or the plurality of struts. Otherconfigurations and/or ranges are also contemplated.

In some embodiments, in the third position the first segment 130 of theplurality of struts of the expandable framework 110 may extend distallyfrom the distal hub 114 substantially parallel to the centrallongitudinal axis to the first bend 132. In the third position, thesecond segment 140 of the plurality of struts of the expandableframework 110 may extend from the first bend 132 radially outwardgenerally perpendicular to the central longitudinal axis toward and/orto the second bend 142. In the third position, the third segment 150 ofthe plurality of struts of the expandable framework 110 may extend fromthe second bend 142 proximally and radially inward toward and/or to thethird bend 152. In some embodiments, in the third position, the fourthsegment 160 of the plurality of struts of the expandable framework 110may extend from the third bend 152 proximally to within the lumen 42 ofthe delivery sheath 40. In some embodiments, in the third position, thefourth segment 160 of the plurality of struts of the expandableframework 110 may extend from the third bend 152 proximally toward theproximal hub 112 disposed within the lumen 42 of the delivery sheath 40.

In some embodiments, in the third position, the distal hub 114 isdisposed proximal of the first bend 132. In some embodiments, in thethird position, the first segment 130 of the plurality of struts and thesecond segment 140 of the plurality of struts may form and/or intersectto form a generally right angle opening toward the interior of theexpandable framework 110. In some embodiments, in the third position,the first segment 130 of the plurality of struts and the second segment140 of the plurality of struts may form and/or intersect to form agenerally right angle opening radially outwardly away from the centrallongitudinal axis. In some embodiments, in the third position, thesecond segment 140 of the plurality of struts and the third segment 150of the plurality of struts may form and/or intersect to form an acuteangle opening radially inwardly toward the interior of the expandableframework 110. In some embodiments, in the third position, the secondsegment 140 of the plurality of struts and the third segment 150 of theplurality of struts may form and/or intersect to form an acute angleopening radially inwardly toward the central longitudinal axis. In someembodiments, in the third position, the third segment 150 of theplurality of struts and the fourth segment 160 of the plurality ofstruts may form and/or intersect to form an obtuse angle openingradially outwardly away from the central longitudinal axis. In someembodiments, in the third position, the second segment 140 of theplurality of struts of the expandable framework 110, if sweptcircumferentially around the central longitudinal axis, may define agenerally planar shape oriented generally perpendicular to the centrallongitudinal axis.

In some embodiments, relative axial translation between the deliverysheath 40 and the expandable framework 110 may expose more of theexpandable framework 110 and/or the plurality of struts in a fourthposition than in the third position, as seen in FIG. 8 . In someembodiments, a third amount of the expandable framework 110 and/or theplurality of struts greater than the second amount may be exposed fromand/or unconstrained by the delivery sheath 40 in the fourth position.In some embodiments, the third amount may be less than about 95% of theaxial length, the volume, the weight, and/or the surface area of theexpandable framework 110 and/or the plurality of struts. In someembodiments, the third amount may be about 60% to about 95% of the axiallength, the volume, the weight, and/or the surface area of theexpandable framework 110 and/or the plurality of struts. Otherconfigurations and/or ranges are also contemplated.

In some embodiments, in the fourth position the first segment 130 of theplurality of struts of the expandable framework 110 may extend distallyfrom the distal hub 114 substantially parallel to the centrallongitudinal axis to the first bend 132. In the fourth position, thesecond segment 140 of the plurality of struts of the expandableframework 110 may extend from the first bend 132 distally and radiallyoutward toward and/or to the second bend 142. In the fourth position,the third segment 150 of the plurality of struts of the expandableframework 110 may extend from the second bend 142 proximally andradially inward toward and/or to the third bend 152. In someembodiments, in the fourth position, the fourth segment 160 of theplurality of struts of the expandable framework 110 may extend from thethird bend 152 proximally toward the proximal hub 112 disposed withinthe lumen 42 of the delivery sheath 40.

In some embodiments, in the fourth position, the distal hub 114 isdisposed proximal of the first bend 132. In some embodiments, in thefourth position, the first segment 130 of the plurality of struts andthe second segment 140 of the plurality of struts may form and/orintersect to form an obtuse angle opening inwardly toward the interiorof the expandable framework 110. In some embodiments, in the fourthposition, the second segment 140 of the plurality of struts and thethird segment 150 of the plurality of struts may form and/or intersectto form an acute angle opening radially inwardly toward the centrallongitudinal axis. In some embodiments, in the fourth position, thethird segment 150 of the plurality of struts and the fourth segment 160of the plurality of struts may form and/or intersect to form an obtuseangle opening radially outwardly away from the central longitudinalaxis. In some embodiments, in the fourth position, the second segment140 of the plurality of struts of the expandable framework 110, if sweptcircumferentially around the central longitudinal axis, may define agenerally conical shape tapering radially outward in a distal directionfrom the first bend 132 toward the second bend 142.

In some embodiments, relative axial translation between the deliverysheath 40 and the expandable framework 110 may expose substantially allof the expandable framework 110 and/or the plurality of struts in afifth position, as seen in FIG. 9 . In some embodiments, a fourth amountof the expandable framework 110 and/or the plurality of struts greaterthan the third amount may be exposed from and/or unconstrained by thedelivery sheath 40 in the fifth position. In some embodiments, thefourth amount may be more than about 95% of the axial length, thevolume, the weight, and/or the surface area of the expandable framework110 and/or the plurality of struts. In some embodiments, the fourthamount may be about 100% of the axial length, the volume, the weight,and/or the surface area of the expandable framework 110 and/or theplurality of struts. Other configurations and/or ranges are alsocontemplated.

In some embodiments, the expandable framework 110 may be in the fullyunconstrained configuration in the fifth position. In some embodiments,in the fully unconstrained configuration, the expandable framework mayhave a maximum radial extent of about 16 millimeters (mm) to about 40mm. In some embodiments, in the fully unconstrained configuration, theexpandable framework may have a maximum radial extent of about 16 mm. Insome embodiments, in the fully unconstrained configuration, theexpandable framework may have a maximum radial extent of about 20 mm. Insome embodiments, in the fully unconstrained configuration, theexpandable framework may have a maximum radial extent of about 25 mm. Insome embodiments, in the fully unconstrained configuration, theexpandable framework may have a maximum radial extent of about 30 mm. Insome embodiments, in the fully unconstrained configuration, theexpandable framework may have a maximum radial extent of about 35 mm. Insome embodiments, in the fully unconstrained configuration, theexpandable framework may have a maximum radial extent of about 40 mm.Other configurations and/or sizes are also contemplated.

In some embodiments, in the fifth position the first segment 130 of theplurality of struts of the expandable framework 110 may extend distallyfrom the distal hub 114 substantially parallel to the centrallongitudinal axis to the first bend 132. In the fifth position, thesecond segment 140 of the plurality of struts of the expandableframework 110 may extend from the first bend 132 distally and radiallyoutward toward and/or to the second bend 142. In the fifth position, thethird segment 150 of the plurality of struts of the expandable framework110 may extend from the second bend 142 proximally and toward and/or tothe third bend 152. In some embodiments, the fifth position, the thirdsegment 150 of the plurality of struts of the expandable framework 110may extend from the second bend 142 proximally generally parallel to thecentral longitudinal axis toward and/or to the third bend 152. In someembodiments, in the fifth position, the fourth segment 160 of theplurality of struts of the expandable framework 110 may extend from thethird bend 152 radially inward toward and/or to the proximal hub 112.

In some embodiments, in the fifth position, the distal hub 114 isdisposed proximal of the first bend 132. In some embodiments, in thefifth position, the first segment 130 of the plurality of struts and thesecond segment 140 of the plurality of struts may form and/or intersectto form an obtuse angle opening inwardly toward the interior of theexpandable framework 110. In some embodiments, in the fifth position,the second segment 140 of the plurality of struts and the third segment150 of the plurality of struts may form and/or intersect to form anacute angle opening radially inwardly toward the central longitudinalaxis. In some embodiments, in the fifth position, the third segment 150of the plurality of struts and the fourth segment 160 of the pluralityof struts may form and/or intersect to form an angle of about 90 degreesor less opening radially inwardly toward the interior of the expandableframework 110. In some embodiments, in the fifth position, the thirdsegment 150 of the plurality of struts and the fourth segment 160 of theplurality of struts may form and/or intersect to form an angle of about90 degrees or less opening radially inwardly toward the centrallongitudinal axis.

A method for occluding the left atrial appendage may comprise advancingthe left atrial appendage closure device 100 into the left atrialappendage of the patient's heart. For example, the left atrial appendageclosure device 100 may be advanced to the left atrial appendage withinthe lumen 42 of the delivery sheath 40 in the fully constrainedconfiguration. The method may include deploying the expandable framework110 from the delivery sheath 40 within the left atrial appendage. Themethod may further include expanding and/or shifting the expandableframework 110 from the fully constrained configuration toward the fullyunconstrained configuration within the left atrial appendage.

As the expandable framework 110 shifts from fully constrained to fullyunconstrained, the expandable framework 110 may transition sequentiallythrough a plurality of positions, as described herein. In someembodiments, in the second position, the expandable framework 110 may bemoved and/or navigated within the patient's heart, the left atrium,and/or the left atrial appendage. In the second position, the expandableframework 110 may form a generally rounded atraumatic shape. In someembodiments, in the second position, the maximum radial extent of theexpandable framework 110 may be about twice or about 200% of a maximumouter extent of a distal end of the delivery sheath 40. In someembodiments, in the second position, the maximum radial extent of theexpandable framework 110 may be about 8 millimeters. Otherconfigurations and/or sizes are also contemplated. In some embodiments,a physician may use the generally rounded atraumatic shape as anavigational tool within the patient's anatomy.

In and/or near the fully unconstrained configuration (e.g., the fifthposition), the expandable framework 110 may be urged into contact with,engaged with, and/or anchored to the lateral wall of the main body ofthe left atrial appendage. In some embodiments, the expandable framework110 may not fully achieve the fully unconstrained configuration (e.g.,the fifth position) due to contact with the wall(s) of the left atrialappendage. However, the inverted shape of the distal portion of theexpandable framework 110 (e.g., the first segment 130, the first bend132, the second segment 140, and the second bend 142) may prevent theexpandable framework 110 from elongating distally, which may compromiselocating the left atrial appendage closure device 100 and/or theexpandable framework 110 within the left atrial appendage, sealing ofthe left atrial appendage closure device 100 and/or the expandableframework 110 with respect to the left atrial appendage, and/oranchoring of the left atrial appendage closure device 100 and/or theexpandable framework 110 within the left atrial appendage. Instead,compressive force applied against the third segment 150 and/or thesecond bend 142 may urge the distal hub 114 proximally toward theproximal hub 112. As such, the final shape of the left atrial appendageclosure device 100 and/or the expandable framework 110 may be morepredictable and locating and anchoring of the left atrial appendageclosure device 100 and/or the expandable framework 110 within the leftatrial appendage may be improved.

In at least some embodiments, the left atrial appendage closure device100 and/or the expandable framework 110 may span across the ostium ofthe left atrial appendage. In some embodiments, the left atrialappendage closure device 100 and/or the expandable framework 110 mayspan completely across the ostium of the left atrial appendage, therebyeffectively removing the left atrial appendage from the circulatorysystem of the patient.

When satisfied with the positioning of the left atrial appendage closuredevice 100 within the left atrial appendage, the core wire 30 may bedisconnected from the left atrial appendage closure device 100, therebyleaving the left atrial appendage closure device 100 disposed at and/orin the left atrial appendage. In some embodiments, disconnecting thecore wire 30 from the left atrial appendage closure device 100 mayinclude rotating the externally threaded distal end of the core wire 30relative to the left atrial appendage closure device 100 and/or theproximal hub 112 to disengage the core wire 30 from the left atrialappendage closure device 100.

In some embodiments, the delivery sheath 40 and/or the core wire 30 mayinclude a keying structure configured to prevent rotation of the corewire 30 relative to the proximal hub 112. In such embodiments, thekeying structure is disengaged prior to rotating the core wire 30relative to the left atrial appendage closure device 100 and/or theproximal hub 112. When the keying structure is engaged, rotation of thecore wire 30 may be transmitted to left atrial appendage closure device100 and/or the expandable framework 110. In some embodiments, rotationof the left atrial appendage closure device 100 and/or the expandableframework 110 may facilitate positioning and/or orientation of the leftatrial appendage closure device 100 and/or the expandable framework 110relative to the left atrial appendage, for example, with respect to anasymmetrical and/or irregular ostium and/or left atrial appendage. Otherconfigurations, purposes, and/or results are also contemplated.

The materials that can be used for the various components of the system(and/or other elements disclosed herein) and the various componentsthereof disclosed herein may include those commonly associated withmedical devices and/or systems. For simplicity purposes, the followingdiscussion refers to the system. However, this is not intended to limitthe devices and methods described herein, as the discussion may beapplied to other elements, members, components, or devices disclosedherein, such as, but not limited to, the left atrial appendage closuredevice, the delivery sheath, the core wire, the expandable framework,the occlusive element, etc. and/or elements or components thereof.

In some embodiments, the system and/or components thereof may be madefrom a metal, metal alloy, polymer (some examples of which are disclosedbelow), a metal-polymer composite, ceramics, combinations thereof, andthe like, or other suitable material.

Some examples of suitable metals and metal alloys include stainlesssteel, such as 444V, 444L, and 314LV stainless steel; mild steel;nickel-titanium alloy such as linear-elastic and/or super-elasticnitinol; other nickel alloys such as nickel-chromium-molybdenum alloys(e.g., UNS: N06625 such as INCONEL® 625, UNS: N06022 such as HASTELLOY®C-22®, UNS: N10276 such as HASTELLOY® C276®, other HASTELLOY® alloys,and the like), nickel-copper alloys (e.g., UNS: N04400 such as MONEL®400, NICKELVAC® 400, NICORROS® 400, and the like),nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R44035 such asMP35-N® and the like), nickel-molybdenum alloys (e.g., UNS: N10665 suchas HASTELLOY® ALLOY B2®), other nickel-chromium alloys, othernickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-ironalloys, other nickel-copper alloys, other nickel-tungsten or tungstenalloys, and the like; cobalt-chromium alloys; cobalt-chromium-molybdenumalloys (e.g., UNS: R44003 such as ELGILOY®, PHYNOX®, and the like);platinum enriched stainless steel; titanium; combinations thereof; andthe like; or any other suitable material.

As alluded to herein, within the family of commercially availablenickel-titanium or nitinol alloys, is a category designated “linearelastic” or “non-super-elastic” which, although may be similar inchemistry to conventional shape memory and super-elastic varieties, mayexhibit distinct and useful mechanical properties. Linear elastic and/ornon-super-elastic nitinol may be distinguished from super elasticnitinol in that the linear elastic and/or non-super-elastic nitinol doesnot display a substantial “superelastic plateau” or “flag region” in itsstress/strain curve like super elastic nitinol does. Instead, in thelinear elastic and/or non-super-elastic nitinol, as recoverable strainincreases, the stress continues to increase in a substantially linear,or a somewhat, but not necessarily entirely linear relationship untilplastic deformation begins or at least in a relationship that is morelinear than the super elastic plateau and/or flag region that may beseen with super elastic nitinol. Thus, for the purposes of thisdisclosure linear elastic and/or non-super-elastic nitinol may also betermed “substantially” linear elastic and/or non-super-elastic nitinol.

In some cases, linear elastic and/or non-super-elastic nitinol may alsobe distinguishable from super-elastic nitinol in that linear elasticand/or non-super-elastic nitinol may accept up to about 2-5% strainwhile remaining substantially elastic (e.g., before plasticallydeforming) whereas super-elastic nitinol may accept up to about 8%strain before plastically deforming. Both of these materials can bedistinguished from other linear elastic materials such as stainlesssteel (that can also be distinguished based on its composition), whichmay accept only about 0.2 to 0.44 percent strain before plasticallydeforming.

In some embodiments, the linear elastic and/or non-super-elasticnickel-titanium alloy is an alloy that does not show anymartensite/austenite phase changes that are detectable by differentialscanning calorimetry (DSC) and dynamic metal thermal analysis (DMTA)analysis over a large temperature range. For example, in someembodiments, there may be no martensite/austenite phase changesdetectable by DSC and DMTA analysis in the range of about −60 degreesCelsius (° C.) to about 120° C. in the linear elastic and/ornon-super-elastic nickel-titanium alloy. The mechanical bendingproperties of such material may therefore be generally inert to theeffect of temperature over this very broad range of temperature. In someembodiments, the mechanical bending properties of the linear elasticand/or non-super-elastic nickel-titanium alloy at ambient or roomtemperature are substantially the same as the mechanical properties atbody temperature, for example, in that they do not display asuper-elastic plateau and/or flag region. In other words, across a broadtemperature range, the linear elastic and/or non-super-elasticnickel-titanium alloy maintains its linear elastic and/ornon-super-elastic characteristics and/or properties.

In some embodiments, the linear elastic and/or non-super-elasticnickel-titanium alloy may be in the range of about 50 to about 60 weightpercent nickel, with the remainder being essentially titanium. In someembodiments, the composition is in the range of about 54 to about 57weight percent nickel. One example of a suitable nickel-titanium alloyis FHP-NT alloy commercially available from Furukawa Techno Material Co.of Kanagawa, Japan. Other suitable materials may include ULTANIUM™(available from Neo-Metrics) and GUM METAL™ (available from Toyota). Insome other embodiments, a superelastic alloy, for example a superelasticnitinol can be used to achieve desired properties.

In at least some embodiments, portions or all of the system and/or otherelements disclosed herein may also be doped with, made of, or otherwiseinclude a radiopaque material. Radiopaque materials are understood to bematerials capable of producing a relatively bright image on afluoroscopy screen or another imaging technique during a medicalprocedure. This relatively bright image aids a user in determining thelocation of the system and/or other elements disclosed herein. Someexamples of radiopaque materials can include, but are not limited to,gold, platinum, palladium, tantalum, tungsten alloy, polymer materialloaded with a radiopaque filler, and the like. Additionally, otherradiopaque marker bands and/or coils may also be incorporated into thedesign of the system and/or other elements disclosed herein to achievethe same result.

In some embodiments, a degree of Magnetic Resonance Imaging (MRI)compatibility is imparted into the system and/or other elementsdisclosed herein. For example, the system and/or components or portionsthereof may be made of a material that does not substantially distortthe image and create substantial artifacts (e.g., gaps in the image).Certain ferromagnetic materials, for example, may not be suitablebecause they may create artifacts in an MRI image. The system orportions thereof, may also be made from a material that the MM machinecan image. Some materials that exhibit these characteristics include,for example, tungsten, cobalt-chromium-molybdenum alloys (e.g., UNS:R44003 such as ELGILOY®, PHYNOX®, and the like),nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R44035 such asMP35-N® and the like), nitinol, and the like, and others.

In some embodiments, the system and/or other elements disclosed hereinmay be made from or include a polymer or other suitable material. Someexamples of suitable polymers may include polytetrafluoroethylene(PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylenepropylene (FEP), polyoxymethylene (POM, for example, DELRIN® availablefrom DuPont), polyether block ester, polyurethane (for example,Polyurethane 85A), polypropylene (PP), polyvinylchloride (PVC),polyether-ester (for example, ARNITEL® available from DSM EngineeringPlastics), ether or ester based copolymers (for example,butylene/poly(alkylene ether) phthalate and/or other polyesterelastomers such as HYTREL® available from DuPont), polyamide (forexample, DURETHAN® available from Bayer or CRISTAMID® available from ElfAtochem), elastomeric polyamides, block polyamide/ethers, polyetherblock amide (PEBA, for example available under the trade name PEBAX®),ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE),MARLEX® high-density polyethylene, MARLEX® low-density polyethylene,linear low density polyethylene (for example REXELL®), polyester,polybutylene terephthalate (PBT), polyethylene terephthalate (PET),polytrimethylene terephthalate, polyethylene naphthalate (PEN),polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI),polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polypraraphenylene terephthalamide (for example, KEVLAR®), polysulfone,nylon, nylon-12 (such as GRILAMID® available from EMS American Grilon),perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin,polystyrene, epoxy, polyvinylidene chloride (PVdC),poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS50A), polycarbonates, ionomers, biocompatible polymers, other suitablematerials, or mixtures, combinations, copolymers thereof, polymer/metalcomposites, and the like. In some embodiments the sheath can be blendedwith a liquid crystal polymer (LCP). For example, the mixture cancontain up to about 6 percent LCP.

In some embodiments, the system and/or other elements disclosed hereinmay include a fabric material disposed over or within the structure. Thefabric material may be composed of a biocompatible material, such apolymeric material or biomaterial, adapted to promote tissue ingrowth.In some embodiments, the fabric material may include a bioabsorbablematerial. Some examples of suitable fabric materials include, but arenot limited to, polyethylene glycol (PEG), nylon,polytetrafluoroethylene (PTFE, ePTFE), a polyolefinic material such as apolyethylene, a polypropylene, polyester, polyurethane, and/or blends orcombinations thereof.

In some embodiments, the system and/or other elements disclosed hereinmay include and/or be formed from a textile material. Some examples ofsuitable textile materials may include synthetic yarns that may be flat,shaped, twisted, textured, pre-shrunk or un-shrunk. Syntheticbiocompatible yarns suitable for use in the present disclosure include,but are not limited to, polyesters, including polyethylene terephthalate(PET) polyesters, polypropylenes, polyethylenes, polyurethanes,polyolefins, polyvinyls, polymethylacetates, polyamides, naphthalenedicarboxylene derivatives, natural silk, and polytetrafluoroethylenes.Moreover, at least one of the synthetic yarns may be a metallic yarn ora glass or ceramic yarn or fiber. Useful metallic yarns include thoseyarns made from or containing stainless steel, platinum, gold, titanium,tantalum or a Ni—Co—Cr-based alloy. The yarns may further includecarbon, glass or ceramic fibers. Desirably, the yarns are made fromthermoplastic materials including, but not limited to, polyesters,polypropylenes, polyethylenes, polyurethanes, polynaphthalenes,polytetrafluoroethylenes, and the like. The yarns may be of themultifilament, monofilament, or spun types. The type and denier of theyarn chosen may be selected in a manner which forms a biocompatible andimplantable prosthesis and, more particularly, a vascular structurehaving desirable properties.

In some embodiments, the system and/or other elements disclosed hereinmay include and/or be treated with a suitable therapeutic agent. Someexamples of suitable therapeutic agents may include anti-thrombogenicagents (such as heparin, heparin derivatives, urokinase, and PPack(dextrophenylalanine proline arginine chloromethylketone));anti-proliferative agents (such as enoxaparin, angiopeptin, monoclonalantibodies capable of blocking smooth muscle cell proliferation,hirudin, and acetylsalicylic acid); anti-inflammatory agents (such asdexamethasone, prednisolone, corticosterone, budesonide, estrogen,sulfasalazine, and mesalamine);antineoplastic/antiproliferative/anti-mitotic agents (such aspaclitaxel, 5-fluorouracil, cisplatin, vinblastine, vincristine,epothilones, endostatin, angiostatin and thymidine kinase inhibitors);anesthetic agents (such as lidocaine, bupivacaine, and ropivacaine);anti-coagulants (such as D-Phe-Pro-Arg chloromethyl ketone, an RGDpeptide-containing compound, heparin, anti-thrombin compounds, plateletreceptor antagonists, anti-thrombin antibodies, anti-platelet receptorantibodies, aspirin, prostaglandin inhibitors, platelet inhibitors, andtick antiplatelet peptides); vascular cell growth promoters (such asgrowth factor inhibitors, growth factor receptor antagonists,transcriptional activators, and translational promoters); vascular cellgrowth inhibitors (such as growth factor inhibitors, growth factorreceptor antagonists, transcriptional repressors, translationalrepressors, replication inhibitors, inhibitory antibodies, antibodiesdirected against growth factors, bifunctional molecules consisting of agrowth factor and a cytotoxin, bifunctional molecules consisting of anantibody and a cytotoxin); cholesterol-lowering agents; vasodilatingagents; and agents which interfere with endogenous vasoactivemechanisms.

It should be understood that this disclosure is, in many respects, onlyillustrative. Changes may be made in details, particularly in matters ofshape, size, and arrangement of steps, without exceeding the scope ofthe disclosure. This may include, to the extent that it is appropriate,the use of any of the features of one example embodiment being used inother embodiments. The disclosure's scope is, of course, defined in thelanguage in which the appended claims are expressed.

What is claimed is:
 1. A medical implant, comprising: an expandableframework having a plurality of struts disposed about a centrallongitudinal axis, the plurality of struts being joined at a proximalhub and a distal hub, wherein the expandable framework includes aproximal shoulder region extending from the proximal hub to a proximalshoulder region end point, and wherein the expandable framework includesa distal shoulder region extending from the distal hub to a distalshoulder region end point, and wherein the portion of the expandableframework extending between the proximal shoulder region end point andthe distal shoulder region end point is substantially parallel to thecentral longitudinal axis.
 2. The medical implant of claim 1, whereinthe expandable framework further includes a proximal shoulder region,wherein the proximal shoulder region includes a first grouping of cellsadjacent to the proximal hub and defining a first row, and wherein afirst cell in the first row of cells includes a first strut segment anda second strut segment joined at a first distal node.
 3. The medicalimplant of claim 2, wherein the first row of cells extendscircumferentially around the central longitudinal axis of the expandableframework.
 4. The medical implant of claim 3, wherein the expandableframework further includes a second grouping of cells defining a secondrow adjacent to the first row, and wherein a second cell in the secondrow of cells includes a third strut segment and a fourth strut segmentjoined at a second distal node.
 5. The medical device of claim 4,wherein the width of at least one cell of the second grouping of cellsis different than the width of the cells defining the first grouping ofcells.
 6. The medical device of claim 5, wherein the width of at leastone cell of the second grouping of cells is wider than the width of thecells defining the first grouping of cells.
 7. The medical implant ofclaim 1, further comprising a membrane disposed along an outer surfaceof the expandable framework.
 8. The medical implant of claim 7, whereinthe membrane extends along the outer surface of the expandable frameworkfrom the proximal hub to a membrane end point, and wherein the membraneend point is positioned along the portion of the expandable frameworkthat is substantially parallel to the central longitudinal axis.
 9. Themedical implant of claim 8, wherein the membrane end point is positionedat the second node of the second grouping of cells.
 10. The medicalimplant of claim 1, wherein the expandable framework further includes aplurality of fixation members disposed thereon.
 11. The medical implantof claim 10, wherein the expandable framework and the plurality offixation members are formed from a unitary tubular member.
 12. Themedical implant of claim 11, wherein at least a portion of the pluralityof fixation members extend through an aperture formed in the membrane.13. The medical implant of claim 1, wherein the plurality of strutsextending between the proximal hub and the distal hub define an interiorvolume of the expandable framework, and wherein the proximal hub islocated outside the interior volume of the expandable framework and thedistal hub is located within the interior volume of the expandableframework.
 14. The medical implant of claim 1, wherein the expandableframework is configured to shift between a first unexpandedconfiguration and an expanded configuration, and wherein when in theexpanded configuration, the distal hub is positioned proximal of adistalmost extent of the expandable framework.
 15. An occlusive implant,comprising: an expandable framework having a plurality of strutsdisposed about a central longitudinal axis, the plurality of strutsbeing joined at a proximal hub and a distal hub, wherein the expandableframework includes a proximal shoulder region extending from theproximal hub to a proximal shoulder region end point, and wherein theexpandable framework includes a distal shoulder region extending fromthe distal hub to a distal shoulder region end point, and wherein theportion of the expandable framework extending between the proximalshoulder region end point and the distal shoulder region end point issubstantially parallel to the central longitudinal axis; a membranedisposed along an outer surface of the expandable framework, wherein themembrane extends along the outer surface of the expandable frameworkfrom the proximal hub to a membrane end point; and a plurality offixation members disposed along the expandable framework.
 16. Theocclusive implant of claim 15, wherein the membrane end point ispositioned along the portion of the expandable framework that issubstantially parallel to the central longitudinal axis.
 17. Theocclusive implant of claim 16, wherein the expandable framework and theplurality of fixation members are formed from a unitary tubular member.18. The occlusive implant of claim 17, wherein at least a portion of theplurality of fixation members extend through an aperture formed in themembrane.
 19. The occlusive implant of claim 15, wherein the pluralityof struts extending between the proximal hub and the distal hub definean interior volume of the expandable framework, and wherein the proximalhub is located outside the interior volume of the expandable frameworkand the distal hub is located within the interior volume of theexpandable framework.
 20. A method for occluding a left atrial appendageof a patient, the method comprising: positioning an occlusive implantadjacent the left atrial appendage, the occlusive implant including; anexpandable framework having a plurality of struts disposed about acentral longitudinal axis, the plurality of struts being joined at aproximal hub and a distal hub, wherein the expandable framework includesa proximal shoulder region extending from the proximal hub to a proximalshoulder region end point, and wherein the expandable framework includesa distal shoulder region extending from the distal hub to a distalshoulder region end point, and wherein the portion of the expandableframework extending between the proximal shoulder region end point andthe distal shoulder region end point is substantially parallel to thecentral longitudinal axis; a membrane disposed along an outer surface ofthe expandable framework, wherein the membrane extends along the outersurface of the expandable framework from the proximal hub to a membraneend point; and a plurality of fixation members disposed along theexpandable framework; and expanding the occlusive implant within theleft atrial appendage such that the membrane extends across an ostium ofthe left atrial appendage.